1. Field of the Invention
This invention relates to connectors for use with intravenous administration lines and systems in the medical field. The invention more particularly relates to an IV quick-connect/disconnect safety assembly that makes it more convenient to attach and detach a patient to and from an IV system.
2. State of the Art
Intravenous therapy has a long history of use in supplying patients with medicament, nourishment or fluids. One of the problems associated with intravenous therapy of ambulatory patients is that the patient cannot be easily disconnected from and reconnected to an intravenous administration line for short periods of time. To safely and easily disconnect the patient for even a short period of time requires the assistance of skilled medical personnel. The ambulatory patient is often required to be attached to the intravenous system and must wheel a stand holding the IV liquid supply wherever the patient goes. Being restricted in this manner can cause the patient to forgo activities of short duration that would be beneficial to the patient.
It is often necessary for hospital staff to move patients from location to location within the hospital in order to perform tests and certain medical treatments. It is not necessary or desirable to have the patient hooked up to the intravenous system during some of these activities. Removing a patient from an intravenous system and re-establishing the patient on the system takes a substantial amount of time even for a medical professional skilled in the techniques of intravenous therapy. With hospital costs rising dramatically there is considerable advantage in a connector device that allows the medical staff to be able to quickly and safely connect and disconnect a patient from an intravenous therapy administration line while expending a minimum amount of time in doing so.
The prior art has addressed some of the above stated problems. For example, patent 4,511,359 issued to Vaillancourt describes a three-part sterile dialysis connection device for home use. The three parts are a male connector which terminates in a catheter tube; a female connector with a hollow needle secured in place and terminating in a flexible tubing; and a molded septum assembly. Vaillancourt places the molded septum assembly in the receiver end of the female connector. The female connector is assembly into place between the male and female connectors, and into friction fit with the male connector, and also causing the sharpened needle in the female connector to pierce the molded septum assembly. The hollow needle provides a path for fluid flow between the two connector parts. When the male and female connectors are separated, the needle is removed from the self-sealing septum, and the septum assembly remains with and covering the male connector because of its friction fit therewith.
Another three-part home dialysis connection device is described in U.S. Pat. No. 4,810,241 issued to Rogers which provides a sterile connection by mechanical and chemical means. The three parts include two connectors, one attached to an influent tube and the other to the catheter tube, and a cylindrical shaped tube in which there is highly absorbent material saturated with antiseptic. The two connectors in turn connect one to each end of the cylinder. As the end connectors are introduced into the central cylinder connector, they are sterilized by the antiseptic in the cylinder and remain in antiseptic contact during the entire time they are being used for dialysis. A sterile environment is maintained on the catheter tubing side of the IV system only for so long as the catheter side tubing is in the connector cylinder. Care must be taken not to let the disinfectant in the cylinder dry out or evaporate.
A somewhat different solution to the problem was taken by U.S. Pat. No. 4,559,043 issued to Whitehouse, et al. which provides a four-piece assembly including a distal connector, a proximate connector, a septum fitting between and held in place by the distal and proximate connectors, and an adapter with a through bore able to accept a hollow needle, the adapter being used in conjunction with the proximate connector. A hollow needle attached to a standard luer extension T which connects to the adapter is pushed through the adapter needle bore and pierces the septum which is held between the proximate and distal connectors, thereby establishing fluid flow. When the hollow needle attached to the luer T is removed, the septum is sealed, but the needle is exposed, presenting a needlestick hazard.
While these devices of the prior art may be effective for their particular purposes, the requirement for a simple, low-cost, quick-connect/disconnect safety assembly is not filled. The prior art does not show a device which has all of the virtues in a single device of being simple and inexpensive to manufacture, providing standard means such as luer fittings for attachment to other devices, and providing means for shielding the needle after use to prevent accidental needlesticks.
My prior U.S. Pat. No. 5,139,483 (the complete disclosure of which is incorporated herein by reference) teaches an IV quick-connect/disconnect device having molded single piece male and female connectors. The male connector has a male luer-lock on one end, a pair of outwardly extending bayonet knobs on a middle portion and a reduced diameter second end which terminates in a resilient septum. The female connector has a female luer-lock on one end and a receiving cylinder with a pair bayonet cut outs on the other; the luer-lock and the cylinder being separated by a wall through which a hollow needle extends that has been insert molded in the wall. The male and female connectors are mated by sliding the reduced diameter second end of the male connector into the receiving cylinder of the female connector, with the bayonet cutouts of the female connector serving as a track for the extended knobs of the male connector. The connectors are locked into place by bringing the male connector as far forward as possible, and then rotating the male connector such that extending knobs move past a restriction in the cutout and click (lock) into place.
This arrangement overcomes many of the disadvantages of the prior art, but it still has its drawbacks. The female connector is fragile due to the bayonet cut outs and these cut outs form a ragged end surface of the female connector when the connectors are uncoupled. The cut outs can actually catch or snag surgical gloves or other medical equipment. Similarly, the bayonet knobs of the male connector present a ragged surface of the male connector when it is uncoupled from the female connector. Moreover, the bayonet knobs on the male connector sometimes extend slightly beyond the outer surface of the female connecter when the connectors are coupled. The extended bayonet knobs of the male connector result in a less than totally smooth surface and this surface can catch, snag and cause tears in surgical gloves, etc. Unfortunately, there is no easy way to avoid this problem in a two piece assembly because molding requirements dictate the bayonet cut outs be located on the female connector and that the knobs which fit into the cut outs be located on the male connector. Indeed, manufacturing considerations have limited the features of these connectors in several ways and the provided features have dictated some inconvenient manufacturing steps. For example, the resilient septum at the second end of the male connector covers a portion of both the inside and the outside wall surface of the second end and is held in place by a thin plastic shrink band. This is not an ideal configuration since the septum and the shrink band are exposed to wear and can be torn. Additionally, the female connectors may carry either an eighteen or twenty gauge needle depending on the type of fluid to be delivered through the connectors, but there is no simple way of distinguishing the larger gauge needles from the smaller gauge needles without direct comparison.